Quantification of Attention in Mismatch Negativity(MMN) under
Controlled Stimulus Parameters

Ha, Eun-Jung; Lim, Dukhwan

doi:2006.2.2.135

Audiol > Volume 2(2); 2006 > Article

Research Paper

Audiology 2006;2(2): 135-140.
Published online: December 31, 2006.
doi: http://doi.org/10.21848/audiol.2006.2.2.135

Mismatch Negativity(MMN) 반응을 이용한 주의집중 정량화에 관한 연구

하은정¹, 임덕환²

¹건국대학교병원 이비인후-두경부외과, 한림대학교 대학원 청각학전공
²한림대학교 언어청각학부 청각학전공, 청각언어연구소

Quantification of Attention in Mismatch Negativity(MMN) under Controlled Stimulus Parameters

Eun-Jung Ha¹, Dukhwan Lim²

¹Department of Otolaryngolog, Konkuk University, Seoul, Graduate Program in Audiology, Hallym University, Chunchon,
²Section of Audiology and Audiology & Speech Pathology Research Institute, Hallym University, Chunchon, Korea

Correspondence

Dukhwan Lim ,Tel: (033) 248-2217, Fax: (02) 6280-9133, Email: dlim@hallym.ac.kr

Received: November 30, 2006; Accepted: December 22, 2006. Published online: December 31, 2006.

ABSTRACT

In this study, Mismatch Negativity (MMN) was explored as a prospective tool for measuring the degree of attention level in normal adult subjects. Both attended and unattended MMN responses of the same subject were analyzed to quantify the degree of attention under the controlled stimulus parameter sets based on frequency and intensity differences. In this paradigm, attended and unattended MMN responses were recorded in 20 adult subjects (male：6, female：14) with normal hearing. The reference frequency of the standard stimulus was 250 Hz and the deviant stimuli were 500, 750, and 1000 Hz. The intensity of the auditory stimuli was systematically varied at 30, 50, and 80 dBnHL. The response area, area difference of the MMN were analyzed to calculate the degree of attentional level (unit voxel area=8.77 ms·μV). The largest differences between the MMN areas of both conditions were obtained with 500 Hz deviant stimulus. The mean area differences were 96.22, 94.91, and 106.90 (ms·μV) with 30, 50, 80 dB of 500 Hz deviants, respectively. From the analysis of the experimental data, the combination of 250 Hz (standard) and 500 Hz (deviant) at 50 dB was concluded as a clinically appropriate value of the protocol for the objective quantification of attention in normal hearing subjects. This MMN protocol could be used as a prospective objective tool for quantifying the level of attention in cases such as CAPD, ADHD, aphasia, and autism.

Key Words: MMN·Attention·Stimulus discrimination.

중심단어: MMN· 주의집중· 자극변별.